Thread knotting apparatus



United States Patent 3,544,144 THREAD KNOTIING APPARATUS Luciano Savio, Via Udine, Pordenone, Italy Filed Dec. 3, 1968, Ser. No. 780,704 Claims priority, application Italy, Dec. 9, 1967, 7,486/ 67 Int. Cl. A01d 59/04 US. Cl. 289-2 Claims ABSTRACT OF THE DISCLOSURE I Thread knotting apparatus which ties the ends of a broken thread into a knot having two knot ends which extend from the knot is provided with a gripper device which is operable in timed relation with the knotting mechanism to grip the two knot ends so that if one or both knot ends should not be cut off by the cutter device associated with the knotting mechanism the thread will be again broken on being drawn away from the knotting mechanism and the knotting mechanism will automatically keep retying the thread until a knot is formed and both knot ends are severed from the knot.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a knotting mechanism for automatically knotting broken threads in spinning, doubling, or winding machines.

Description of the prior art When a thread breaks in a spinning, doubling, or winding machine comprising an automatic thread breakage eliminator, the two ends of the broken thread are carried by means of an automatically operating, e.g. a pneumatic, thread gripping device to an automatic knotting mechanism by which the broken ends are tied into a knot. The two knot ends, that is the freely extending terminal portions of the knotted thread ends, are cut off as close to the knot as possible at the end of the knotting operation, by means of an automatically operating severing device incorporated in the knotting mechanism.

In the case of such devices, which are known in a number of different structural designs, it occurs relatively often that one knot end, or both knot ends, are not cut off by the severing device. The knot ends left on the knotted thread, occasionally having a length of approximately 10 to cms., can then cause trouble in the machines during the further processing of the spun, doubled, or wound yarn, and may produce faults in the fabric woven or knitted with the yarn.

It is an object of the invention to eliminate or greatly to reduce these drawbacks, that is to prevent the retention of uncut knot ends on the knotted thread returned to the spinning, doubling, or Winding machine, in reliable manner and with a minimum of technological investment.

SUMMARY According to the invention there is provided a knotting apparatus for automatically knotting broken threads in spinning, doubling, or winding machines, comprising knotting mechanism operable to tie the ends of a broken thread into a knot having two knot ends extending therefrom and including cutter means operable to sever the knot ends from the knot, driving means operable to effect operation of the knotting mechanism, a normally inactive gripper device operable automatically during each knotting operation to grip the knot ends and actuating means operable in timed relation with the operation of the driving means to render the gripper device active to effect gripping of the knot ends.

With such an apparatus, the knot ends formed during each knotting operation are gripped and held fast by the gripper device coming into action automatically. When both knot ends have been correctly gripped and have been severed by the severing device, the thread knotted and severed from the gripper knot ends, can be returned directly to the spinning, doubling, or winding machine, and the latter can resume its run. If however even one of the two knot ends is gripped incorrectly, so that it is not severed from the knot, the knotted thread is broken again during its return to the spinning, doubling, or winding machine on resumption of its run, because it is held back by the uncut knot end still gripped by the gripper device. The automatic thread breakage eliminator accordingly comes into action again and initiates another knotting operation. The knotting operation is thus repeated automatically until the severing device of the knotter severs both knot ends.

In one embodiment of the invention, the gripper device is in the inactive position thereof during a knotting operation and is brought into the active knot end gripping condition thereof at the end of the knotting operation, just before the end of the knotting operation or after the termination of he knotting operation.

The activating means for the gripper device may be operable by said driving means.

In a preferred embodiment of the invention, the gripping device comprises first and second relatively movable clamping jaws which in the inactive condition of the gripper device are located on opposite sides of the path of the knot ends of a knot tied by the knotting mechanism. At least one of the clamping jaws is preferably freely pivotable relative to the other. With this form of the apparatus the knot ends are both gripped and held fast reliably between the clamping jaws, even if the thread ends are of slightly different thickness. According to a further feature of the invention, one clamping jaw is provided with a groove which extends in a direction transverse to the knot ends, and the other clamping jaw is engageable in said groove.

In an embodiment of the invention in which the knotting mechanism includes a pneumatic thread interception device operable to locate the ends of a broken thread in ingress and egress slots provided in the knotting mechanism, the first clamping jaw is preferably arranged on the outer side of the knotting mechanism closely below the lower extremities of the egress slots, and the second clamping jaw is disposed above the first clamping jaw and is vertically and reciprocatingly displaceable relative to the first clamping jaw.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational of a knotting apparatus according to the invention and illustrates a gripping device embodied therein in the closed condition of the gripping device,

FIG. 2 is an elevation of a part of the apparatus of FIG. 1, with the gripping device in the opened condition thereof,

FIG. 3 is a top plan view of FIG. 1, and

FIG. 4 is an end view, partly in section, of a part of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT The knotting apparatus, indicated generally by the reference numeral 1, is incorporated in spinning, doubling or winding or analogous frames which include an automatic thread breakage eliminator. If a thread breakage occurs, the two ends F1 and F2, FIG. 3, of the broken thread are laid transversely from above into and though the knotting apparatus 1 by means of an automatically operated pneumatic thread gripping or interception device, which is known per se, e.g. from British patent specification No. 1,134,583, and is not illustrated in the drawings. The thread ends F1 and F2 are concomittantly inserted into an ingress slot, not shown, inthe rear side of the knotting apparatus 1, and into a corresponding egress slot 103, 203 FIGS. 1 and 2, in the front side of the knotter, by means of a stationary thread guide element 2 projecting above the knotting apparatus. The thread ends F1 and F2 are thereupon automatically knotted with each other by the knotting apparatus. The terminal parts S1, S2, FIGS. 1 to 3, which extend from the knot K, FIG. 3, so formed, hang down from the knotting apparatus 1 through the egress slot 103, 203, are referred to as the knot ends. The knot ends S1, S2 are cut off as close as possible to the knot K at the end of the knotting operation by means of an automatically operating severing device incorporated in the knotting apparatus 1.

The mechanism for knotting the thread ends F, F2 and the device for the severing of the knot ends S1, S2 fromthe knotted thread, as well as the other parts of the thread breakage eliminator, specifically the control device for the automatic starting of the knotter drive system, are know per se in difierent structural embodiments of the knotting apparatus and are not described in detail.

In the embodiment illustrated, the knotting apparatus 1 is fastened on a part 106 of the machine frame 6 by means of a bracket 4 and a screw 5, FIG. 3. The knotting mechanism is actuated by means of a lever 7 projecting from beneath the knotting apparatus 1. On the machine frame 6 a driving lever 9, which carries an adjustable plunger 10 for co-operation with an actuating lever 7, 'is arranged to swivel about a pivot pin 8, FIGS. 3 and 4.

A torsion spring 11 positioned around the pin 8 holds 7 the driving lever 9 in its idle position, pivoted toward the left as viewed in FIGS. 1 to .3, in which position the lever 9 bears against an adjustable abutment 12, FIGS.

1 and 3, secured on the machine frame. During operation of the knotting apparatus, the driving lever 9 is caused to pivot against the action of the spring 11, towards the right; as viewed in FIGS. 1 to 3, by means of a tension rod 13, FIGS. 3 and 4. After an idle movement L. FIG. 1, the plunger 10 engages the actuating lever 7 and causes pivotal movement thereof, to the position illustrated in FIG. 2. This actuates the knotting mechanism, which forms the knot K and by means of the incorporated severclamping jaw 15 situated above the jaw 14, the jaw 15 being vertically and reciprocatingly displaceable. The secone or upper'clamping jaw 15 is pendularly suspended from a pivot pin 16 on a rocking lever 17, pivoted on a pivot spindle 18 at the side of the knotting apparatus. The rocking lever 17 is provided with a downwardly directed plunger or projection 117 which co-operates with the upper side of an actuating member 19 projecting from and adjustably fastened on the driving lever 9. The actuating member 19 is cranked or bent at its unattached extremity to form an oblique run-on surface 119,and an adjacent and appropriately raised bearing surface 219 for the plunger or projection 117 of the rocking lever 17.

The second or upper clamping jaw 15 pendularly arranged on the rocking lever 17 possesses chamfered and downwardly divergent lateral edges 115, 215, FIG. 1, which in elevation extend transversely through the corresponding egress slots 103, 203, as is apparent from FIGS.

1 and 2. The upper effective surface of the stationary first or lower clamping jaw 14 is approximately trough-shaped. The lower extremity of the second or upper clamping jaw 15 is bar-shaped and can engage in the trough of jaw 14 as illustrated in FIG. 4.

Between the rocking lever 17 and the knotting apparatus 1 is a compression spring 20, FIGS. 1 to 3, which downwardly pivots the rocking lever 17 in the idle position of the driving lever 9 and of the knotting apparatus, 1, and thereby presses the second or upper clamping jaw 15, which is articulated at 16 to the lever 17, against the stationary first or lower clamping jaw 14. The oblique run-on surface 119 of the actuating member 19 is situated a short distance in advance of the plunger or projection 117 of the rocking lever 17, as illustrated in FIG. 1. 1

When a thread breakage occurs, the thread ends F1, F2 inserted from above through theknotting apparatus 1 into the egress slots 103, 203, slip down on the oblique divergent lateral edges 115, 215 of the second or upper clamping jaw 15 and are laid on the stationary first or lower clamping jaw 14 on opposite sides of the second or upper'clamping jaw 15. A continuous suction action is exerted on the knot ends S1, S2 by means of a pneumatic thread interception device, e.g. a device as described in British patent specification No. 1,134,583.

Right at the beginning of the subsequent inward pivotal displacement of the driving lever 9 to the right as viewed in FIGS, 1 and 2, that is whilst the plunger 10 which co-operates with the actuating lever 7 traverses the idle movement L, the run-on surface 119 of the actuating member 19 comes into contact with the lower plunger or projection 117 of the rocking lever 17 and lifts the lever 17 against the action of the spring 20. The second or upper clamping jaw 15 is accordingly lifted off the stationary first or lower clamping jaw 14, as illustrated in FIG. 2. The knot ends S1, S2 which until then had been situated on the opposite sides of the second or upper clamping jaw 15 and, which are permanently acted upon by the suction draught of the pneumatic thread interception device, are displaced automatically as a result of the suction, towards each other on the stationary first or lower clamping jaw 14, that is inwards, and are thus positioned under the lifted second or upper clamping jaw 15, as shown in FIG. 2.

During the continued inward pivotal displacement of the driving lever 9, by means of which the knotting apparatus 1 is actuated through the plunger 10 and the actuating lever 7, the plunger or projection 117 of the rocking lever 17, and consequently also the upper clamping jaw 15, is held in its raised position illustrated in FIG. 2, by means of the raised bearing surface 219 of the actuating member 19. The knot ends S1, S2 lying between the. opened clamping jaws 14 and 15 accordingly retain their freedom of movement advantageous for the forming of a perfect knot K throughout the knotting operation.

On termination of the knotting operation, the driving lever 9 is deflected to its idle position, FIGS. 1 and 3. At the end of the deflection of the driving lever 9, that is after the plunger 10 has been separated from the retreating actuating lever 7, the oblique run-on surface 119 of the actuating branch 19 is drawn away from the plunger or projection 117 of the rocking lever 17 and the lever 17 is pivoted by the action of the spring 20 to its idle position illustrated in FIGS. 1 and 4. Consequently, the second or upper clamping jaw 15 is pressed against the stationary first or lower clamping jaw 14. The ot ends- S1, S2 which extend from the knot K and hang down from the knotting apparatus 1 through the egress slot 103, 203, are thereby gripped and held fast between the closed clamping jaws 14, 15, as illustrated in FIG. 1. The engagement of the second or upper clamping jaw 15 in the trough of the first or lower clamping jaw 14 assures a particularly firm grip on the knot ends S1, S2.

When both knot ends S1, S2 are correctly gripped and are cut off by the severing device embodied in the knotting apparatus 1 at the end of the knotting operation, the knotted thread may unimpededly and in conventional manner be returned to the spinning, doubling or winding mechanism and resume its run, since it has been severed from the clamped knot ends S1, S2. If, on the contrary, the severing device does not operate correctly, that is it fails to cut off even only one of the knot ends S1, S2, the knotted thread is broken again during its return to the spinning, doubling or winding mechanism and upon resumption of its run, because it is held fast by the uncut knot end S1, S2 gripped between the clamping jaws 14, 15. The automatic thread breakage eliminator accordingly immediately initiates another knotting operation, which is repeated automatically in the manner described above until both ends S1, S2 of the formed knot K have been out 05.

I claim:

1. Knotting apparatus for automatically knotting broken threads in spinning, doubling, or winding machines, comprising knotting mechanism operable to tie the ends of a broken thread into a knot having two knot ends extending therefrom and including cutter means operable to sever the knot ends from the knot, drivingmeans operable to elfect operation of the knotting mechanism, a normally inactive gripper device operable automatically during each knotting operation to grip the knot ends, and actuating means operable in timed relation with the operation of the driving means to render the gripper device active to effect gripping of the knot ends.

2. Knotting apparatus according to claim 1, wherein the gripper device is in the inactive position thereof during a knotting operation and is brought into the active knot end gripping condition thereof at the end of the knotting operation, just before the end of the knotting operation or after the termination of the knotting operation.

3. Knotting apparatus according to claim 1, wherein the actuating means for the gripper device is operable by said driving means.

4. Knotting apparatus according to claim 3, wherein the gripping device comprises first and second relatively movable clamping jaws which in the inactive condition of the gripper device are located on opposite sides of the path of the knot ends of a knot tied by the knotting mechanism.

5. Knotting apparatus according to claim 4, wherein at least one clamping jaw is freely pivotable relative to the other.

6. Knotting apparatus according to claim 4, wherein one clamping jaw is provided with a groove which extends in a direction transverse to the knot ends, and the other clamping jaw is engageable in said groove.

7. Knotting apparatus according to claim 6, wherein the knotting mechanism includes a pneumatic thread interception device operable to locate the ends of a broken thread in ingress and egress slots provided in the knotting mechanism, wherein the first clamping jaw is arranged on the outer side of the knotting mechanism closely below the lower extremities of the egress slots, and the second clamping jaw is disposed above the first clamping jaw and is vertically and reciprocatingly displaceable relative to the first clamping jaw.

8. Knotting apparatus according to claim 7, wherein the second clamping jaw is pendularly suspended on an upwardly and downwardly pivotable rocking lever.

9. Knotting apparatus according to claim 8, wherein the second clamping jaw is provided with oblique and downwardly diverging lateral thread guiding edges bridging the egress slots.

10. Knotting apparatus according to claim 7, wherein the driving means for the knotting mechanism comprises an actuating lever co-operating with a driving lever, and the actuating means for the gripper device comprises a rocking lever carrying the second clamping jaw and provided with a plunger-like projection, an actuating member movable with said actuating lever, a spring urging said projection into engagement with the actuating member, and a cam profile carried by the actuating member and operable on movement of the actuating member by the driving lever to permit said pivoted lever to move the second clamping jaw into and out of gripping relation with the first clamping jaw.

11. Knotting apparatus according to claim 5, wherein one clamping jaw is provided with a groove which extends in a direction transverse to the knot ends, and the other clamping jaw is engageable in said groove.

12. Knotting apparatus according to claim 11, wherein the knotting mechanism includes a pneumatic thread interception device operable to locate the ends of a broken thread in ingress and egress slots provided in the knotting mechanism, wherein the first clamping jaw is arranged on the outer side of the knotting mechanism closely below the lower extremities of the egress slots, and the second clamping jaw is disposed above the first clamping jaw and is vertically and reciprocatingly displaceable relative to the first clamping jaw.

13. Knotting apparatus according to claim 12, wherein the second clamping jaw is pendularly suspended on an upwardly and downwardly pivotable rocking lever.

14. Knotting apparatus according to claim 13, wherein the second clamping jaw is provided with oblique and downwardly diverging lateral thread guiding edges bridging the egress slots.

15. Knotting apparatus according to claim 14, wherein the driving means for the knotting mechanism comprises an actuating lever co-operating with a driving lever, and the actuating means for the gripper device comprises a rocking lever carrying the second clamping jaw and provided with a plunger-like projection, an actuating member movable with said actuating lever, a spring urging said projection into engagement with the actuating member, and a cam profile carried by the actuating member and operable on movement of the actuating member by the driving lever to permit said pivoted lever to move the second clamping jaw into and out of gripping relation with the first clamping jaw.

References Cited UNITED STATES PATENTS LOUIS K. RIMRODT, Primary Examiner 

